MAHALAKSHMI
ENGINEERING COLLEGE
TIRUCHIRAPPALLI – 621213
Sub Code: GE 6253
Subject: ENGINEERING MECHANICS
Semester: II
Unit – I: BASICS AND
STATICS OF PARTICLES
PART A
1. Define Coplanar & concurrent forces. (AU JUN’10, DEC’10, DEC’12)
2. What is the different between a resultant force and equilibrant force? (AU
DEC’10,JUN’12)
3. State the necessary and sufficient conditions for static equilibrium of a particle in two
dimensions. (AU JUN’12, DEC’11)
4. What is unit vector? (AU JUN’09)
M.P.KEDARNATH / Asst Prof - Mechanical
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5. State Lame’s theorem. (AU JUN’12,DEC 10)
6. A force
acts through the origin. What is the magnitude of the force and
the angle it makes with X, Y and Z axis? (AU DEC’09,JUN 09)
7. State Varignon’s Theorem? (AU MAY’11)
If a number of coplanar forces are acting simultaneously on a body , the algebraic sum
of the moments of all the forces about any point is equal to the moment of resultant force
about the same point.
M.P.KEDARNATH / Asst Prof - Mechanical
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8. Find the magnitude of the resultant of the two concurrent forces of magnitude 60 kN and
40 kN with an included angle of 70o between them. (AU MAY’11)
9. A force of magnitude 500N is passing through the origin and a point A (0.2, 1, 0) m. write
the couple form of the force. (AU DEC’11)
10. State the principal of transmissibility of forces with simple sketch. (AU JUN’09, DEC’11)
M.P.KEDARNATH / Asst Prof - Mechanical
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PART B
1. Determine the resultant of the concurrent force system shown in the following
Figure. (AU JUN’10, DEC’10, DEC’12)
M.P.KEDARNATH / Asst Prof - Mechanical
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2.
The following figure shows a 10 kg lamp supported by two cables AB and AC. Find
the tension in each cable. (AU JUN’10, DEC’10, DEC’12)
M.P.KEDARNATH / Asst Prof - Mechanical
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3.
The truck is to be towed using two ropes. Determine the magnitudes of forces FA
and FB acting on each rope in order to develop a resultant force of 950N directed
along the positive X-axis. (AU MAY’11, JUN’12)
.
M.P.KEDARNATH / Asst Prof - Mechanical
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4.
Determine the magnitude and angle
Equilibrium (AU MAY’11, JUN’12)
M.P.KEDARNATH / Asst Prof - Mechanical
and F so that particle shown in figure, is in
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5. ABCDE is a light string whose end A is fixed. The weights W 1 and W 2 are attached to the
string at B & C and the string passes round a small smooth wheel at D carrying a weight
40KN at the free end E. In the position of equilibrium, BC is horizontal and AB and CD
make angles 150° and 120° with horizontal. (AU DEC’12)
Find (i) the tensions in AB, BC and DE of the given string (ii) magnitudes of W 1 and W 2.
M.P.KEDARNATH / Asst Prof - Mechanical
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6. Find the magnitude and position of the resultant of the system of forces shown in
Figure below. (AU JUN’09,DEC ‘ 10)
M.P.KEDARNATH / Asst Prof - Mechanical
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7.
A horizontal force P normal to the wall holds the cylinder in the position shown in figure
below. Determine the magnitude of P and the tension in each cable. (AU DEC’12)
M.P.KEDARNATH / Asst Prof - Mechanical
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M.P.KEDARNATH / Asst Prof - Mechanical
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8.
Figure below shows three cables AB, AC, AD that are used to support the end of a
sign which exerts a force of
at A. Determine the force develop
in each cable. (AU DEC’11)
M.P.KEDARNATH / Asst Prof - Mechanical
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M.P.KEDARNATH / Asst Prof - Mechanical
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9.
In the figure shown, three wires are joined at D.
Tow ends A and B are on the wall and the other end C on the ground. The wire CD is
vertical. A force of 60 KN is applied at ‘D’ and it passes through a point E on the ground as
shown in figure. Find the forces in all the three wires. (AU JUN’10, JUN’12)
M.P.KEDARNATH / Asst Prof - Mechanical
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M.P.KEDARNATH / Asst Prof - Mechanical
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10.
Two forces act upon a tripod at ‘P’ as shown in figure. The force 8 kN is parallel to xaxis and the force 16kN is parallel to y – axis. (AU MAY’11,JUN ’12 )
Determine the forces acting at the legs of tripod if the legs rest on ground at A, B, and C
whose coordinates with respect to O are given .The height of the P above the origin is 10m.
M.P.KEDARNATH / Asst Prof - Mechanical
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M.P.KEDARNATH / Asst Prof - Mechanical
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11. Forces R, S, T, U are collinear. Forces R and T act from left to right. Forces S and
U act right to left. Magnitudes of the forces R, S, T, U are 40N, 45N, 50N and 55N
respectively. Find the resultant of R, S, T, U. (AU JUN’09)
11. State the parallelogram law of forces (AU JUN’09, DEC 12)
12. Distinguish between scalar and vector quantities. (AU JUN’09, DEC 10)
M.P.KEDARNATH / Asst Prof - Mechanical
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